Key guard



Jn 1jne 3, 1930. T. w. KIUYPFER l,761 ,l3l

KEY GUARIJ' Filed Nov. 28, 1927 I Inventor neodore M Ku afcr By I 'Attorney Patented June 3, 1930 eaTEnT- THEODORE W. KUPFER, OF ROCHESTER,YORK KEY GUARD Application filed November 28, 1927. Serial No. 236,181.

The object of this invention is to provide an improved form of keyguards for use on the inside of door locks to hold the key with whichthe door has been locked in place in the I] lock and prevent theinsertion of another key into the look from the outside of'the door.

Another object of this invention is to so construct the key guard thatthe key is held rigidly in place in the lock and cannot be 10 turned orin any way moved after the locking member of the key guard has beenbrought in engagement therewith.

These and other objects of this invention will be fully illustrated inthe drawing, described in the specification and pointed out in theclaims at the end thereof. I

In the accompanying drawing:

Figure 1 is a front elevation of the improved key' guard asit appearswhen attached to the lock of a door.

Figure 2 is a side elevation of the key guard attached to a door. 7

FigureB is a' front elevation of a portion of the key guard with itslocking member moved into engagement with the key of the lock.

' Figure 4 is a detail perspective view of the key guard as it appearsbefore it is attached to the lock of a door. v

In the several figures of the drawing, like reference numerals indicatelike parts.

The key guard forming the subject matter of this invention is made to beattached to the door so as to form a permanent fixture in combinationwiththe lock. This is in distinction of other key guards which must beattached and detached every time the lock is locked or unlocked.

-As illustrated in the figures of thedrawing, the key guard comprises astationary guide frame which is made up of the parallel upright members1 and 2 that are oined at the top by the loop'3 and at'the bottom by themounting and clamping member 4. The loop 3 isslightly offset to thefront of the frame and is adapted to encircle the upper portion of theperiphery of the shank 5 of the door knob 6. For the purpose ofattaching the frame of the key guard to the shank 5, the mounting andclamping member 4 is removed member 4.

from the free ends of the parallel guidemembers 1 and 2 to allow theguide frameto engage over the shank and slide down over it until theloop 3 at the top of theframeongages the top of the shank '5. I

The mounting and clamping member 4; comprises a metal strap whichencircles a spacing block 5 leaving enough space between the spacingblock and the inside of the metal strap to permitthe insertion of theends of the 80 upright guide members 1 and 2 after the wire frame hasbeen placed over the door knob shank as above pointed out. After themounting and clamping member has again been attach-ed to'the lower endof the guide '65 frame it is fastened in place on the face of the doorbelow the look by means of the screw 6 which passesthru a hole providedcentrally of both themetal strap and the spar I ing block that make upthe inountlng and clamping member 6. In fastening the clamping andmounting member to thedoor the ends of. the parallel guide members 1 and2 are at the same time clamped in place in the mounting member so thatthe guide framo is firmly held in a; verticalposition betweenthe shank50f the door knob and the mounting On the guide frame above describedismounted to "slide the locking frame with '80 which the handle of the keyof the lock may be held or released fromthe lock. This looking framecomprises a horizontal lock ng member-7 located at the top of thelocklng frame, the gripping member 8 and 9 intervmediate of the lockingframe and the handle 10 at the bottom of the locking frame. Allof thesemembers are preferably formed np froma single piece of wire whichencircles the guide members 1 and 2 bothat the top and 0 bottom of thelocking frame to hold the looking frame in sliding engagementavith theguide frame. The gripping members 8 and 9 form the intermediate sectionof the locking frame and while gripping member 9 1s rigid with thelocking member 7 at the top andthe handle 10 at the bottom, grippingmember 8 is onl rigid with the handle 10 at the bottom and is notconnected with the locking member 7at the top. Instead the upper freeend of the grippin member partially encircles the guide mem er 1 andthen extends across the back of the guide frame to the back of the guidemember 2 and projects slightly beyond it. The gripping members are bentangularly to project from the center of the locking frame below thelooking member, and thus form the gripping jaws 11 and 12 which serve tohold the locking member 7 in engagement with the handle of the key ofthe look as will hereinafter be described. Gripping jaw 11 forms a partof the gripping member 8, which as previously pointed out, can yield toone side at the upper end so that when the shank 13 of a key is forcedthru between the two gripping jaws, the gripping jaw 11 can swing to oneside until the shank has passed the jaws when it will spring back intonormal position in back of the shank. During this swinging motion of theyielding member 8, an extension provided at the top thereof andprojecting from one side of the guide frame to the other in back of theguide frame, serves to hold the yielding member in place against apossible movement away from in front of the guide frame and guides theyielding member 8 back to its normal position after the shank of the keyhas passed from one end of the gripping jaw to the other.

As illustrated in Figures 1 and 3 the guide frame is mounted in front ofthe look so that the keyhole 14 is located between the parallel guidemembers 1 and 2. The key of the lock is thus free to be inserted orwithdrawn from the lock unless the locking member 7 is held inengagement with the handle 15 of the key. This is done after the lockhas been locked with the key and the handle 15 thereof has beenturnedinto a horizontal position as illustrated in full lines in Figures2 and 3. To look the key in place in'this position the locking frame ofthe key guard is moved down from the dotted line position illustrated inFigure 2 to the full line position. In so doing the gripping jaws 11 and12 are moved past'the key shank 13 with the result that the gripping jaw11 is forced to one side but swings back into the place below the keyshank so that the key shank is held in place In the space left freebetween the top of the gripping jaws 11 and 12, and the under side ofthe locking member 7. While the gripping jaws 11 and 12 engage the underside of the key shank, the locking member 7 engages the handle of thekey holds it against rotation so that the key shank cannot be turned inthe look from the outside of the door and the key forced out of the lockto make room foranother one.

I claim:

1. A key guard comprising a stationary guide on the inside of the doorengagnig over the handle of the door at the top and fastened to the doorat the bottom, a guard mounted to slide on said guide and having atongue adapted to engage the handle of the key and prevent its beingturned from the outside of the door, said guard having two aws adaptedto engage below the shank of the key to hold the tongue down on the keyhandle, said jaws being adapted to close in front of the key hole of thelook when the tongue is holding a key in place therein, said jawspreventing vision through the keyhole.

2. A key guard comprising a stationary guide on the inside of the doorengaging over the handle of the door at the top and fastened to the doorat the bottom, a guard mounted to slide on said guide and having atongue adapted to engage the handle of the key and prevent its beingturned from the outside of the door, said guard having two jaws adaptedto engage below the shank of the key to hold the tongue down on the keyhandle, one of said jaws being spring pressed to permit the jaws to openand close while being moved past the shank of the key.

3. A key guard comprising a stationary wire guide on the inside of thedoor engaging 6 over the handle of the door at the top and fastened tothe door at the bottom, a wire guard mountedto slide on said guide andhaving a rigid engagement therewith at four points, the upper pair ofpoints being spaced a long distance from the lower pair of points, atongue formed on said guard and being adapted to engage the handle ofthe key to prevent its being turned from the outside of the door.

4. A key guard comprising a stationary wire guide on the inside of thedoor engaging over the handle of the door at the top and fastened to thedoor at the bottom, a wire guard mounted to slide on said guide andhaving a rigid engagement therewith at four points, the upper pair ofpoints being spaced a long distance from the lower pair of points, bybeing looped around the member of said guide, said guard extending outat the bottom to form a handle and extending out at the top to form atongue adapted to engage the handle of the key to keep it from turningand having a pair of jaws formed between the top and bottom, said jawsbeing adapted to engage above or below the shank of the key, one of saidjaws being spring pressed to permit the jaws to open and close whilebeing moved past the shank of the key.

5. A key guard comprising a stationary wire guide on the inside of thedoor engaging over the handle of the door at the top and fastened to thedoor at the bottom, a wire guard mounted to slide on said guide andhaving a rigid engagement therewith at four points, a pair of jawsformed therein, said jaws being adapted to engage above or below theshank of the key, one of said jaws being spring pressed to permit thejaws to open and close While being moved past the shank of the key.

6. A key guard comprising a stationary Wire guide on the inside of thedoor engaging over the handle of the door at the top and fastened to thedoor at the bottom, and having two parallel members placed on oppositesides of the key and key hole, a Wire guard mounted to slide on saidguide and having a close engagement with each of said members at twopoints, spaced apart so as to give a long bearing thereon, a tongueformed on said guard and being adapted to engage the handle of the keyto prevent its being turned from the outside of the door.

In testimony whereof I aflix my signature.

THEODORE W. KUPFER.

